University of Exeter

Scientists have long puzzled over what, exactly, is destroying the global honeybee population. Now, researchers say they have new insights into what's behind one of the viruses contributing to the overall decline: humans.

According to a study published Thursday in Science and led by researchers from the University of Exeter and UC Berkeley, the global honeybee trade has helped spread a deadly disease from Europe to other countries across the world.

The researchers explained that those transporting bees are bringing Deformed Wing Virus and the Varrao mite, a parasite that attacks bees, across borders. Separately, the two afflictions aren't all that harmful to bees, but together they are deadly. Lead authorLena Wilfert told VICE that she and her team set out to figure out what's causing the lethal pairing to spread across bee populations.


"It’s been known for a while that the combination of Deformed Wing Virus (DWV) and the Varroa mite are really bad news for honeybees…we wanted to know how the diseases they cause had spread globally, and which populations are driving the epidemic at a global level," she said.


Wilfert added in a statement: "This is the first study to conclude that Europe is the backbone of the global spread of the bee killing combination of Deformed Wing Virus and Varroa. This demonstrates that the spread of this combination is largely manmade."

The team concluded that people must be behind the international spread of the disease, because researchers found that bees in nations far from Europe (like New Zealand) were afflicted by a virus that had started on the continent.

This conclusion, at least, means that there are steps we can take to protect bees. The authors write, "to reduce the negative effects of DWV on beekeeping and wild pollinators, tighter controls, such as mandatory health screenings and regulated movement of honeybees across borders, should be imposed." Good idea.


Danielle Wiener-Bronner is a news reporter.